Diabetic retinopathy

Diabetic retinopathy (die-uh-BET-ik ret-ih-NOP-uh-thee) is a complication of diabetes that affects the eyes. It's caused by damage to the blood vessels of the light-sensitive tissue at the back of the eye (retina).

At first, diabetic retinopathy may cause no symptoms or only mild vision problems. Eventually, however, diabetic retinopathy can result in blindness.

Diabetic retinopathy can develop in anyone who has type 1 diabetes or type 2 diabetes. The longer you have diabetes, and the less controlled your blood sugar is, the more likely you are to develop diabetic retinopathy.

To protect your vision, take prevention seriously. Start by carefully controlling your blood sugar level and scheduling yearly eye exams.

Symptoms Causes Risk factors Complications Prevention

It's possible to have diabetic retinopathy and not know it. In fact, it's uncommon to have symptoms in the early stages of diabetic retinopathy.

As the condition progresses, diabetic retinopathy symptoms may include:

  • Spots or dark strings floating in your vision (floaters)
  • Blurred vision
  • Fluctuating vision
  • Dark or empty areas in your vision
  • Vision loss
  • Difficulty with color perception

Diabetic retinopathy usually affects both eyes.

Diabetic retinopathy may be classified as early or advanced, depending on your signs and symptoms.

  • Early diabetic retinopathy. This type of diabetic retinopathy is called nonproliferative diabetic retinopathy (NPDR). It's called that because at this point, new blood vessels aren't growing (proliferating). NPDR can be described as mild, moderate or severe. When you have NPDR, the walls of the blood vessels in your retina weaken. Tiny bulges (called microaneurysms) protrude from the vessel walls, sometimes leaking or oozing fluid and blood into the retina. As the condition progresses, the smaller vessels may close and the larger retinal vessels may begin to dilate and become irregular in diameter. Nerve fibers in the retina may begin to swell. Sometimes the central part of the retina (macula) begins to swell, too. This is known as macular edema.
  • Advanced diabetic retinopathy. Proliferative diabetic retinopathy (PDR) is the most severe type of diabetic retinopathy. It's called proliferative because at this stage, new blood vessels begin to grow in the retina. These new blood vessels are abnormal. They may grow or leak into the clear, jelly-like substance that fills the center of your eye (vitreous). Eventually, scar tissue stimulated by the growth of new blood vessels may cause the retina to detach from the back of your eye. If the new blood vessels interfere with the normal flow of fluid out of the eye, pressure may build up in the eyeball, causing glaucoma. This can damage the nerve that carries images from your eye to your brain (optic nerve).

When to see a doctor

Careful management of your diabetes is the best way to prevent vision loss. If you have diabetes, see your eye doctor for a yearly dilated eye exam — even if your vision seems fine — because it's important to detect diabetic retinopathy in the early stages. If you become pregnant, your eye doctor may recommend additional eye exams throughout your pregnancy, because pregnancy can sometimes worsen diabetic retinopathy.

Contact your eye doctor right away if you experience sudden vision changes or your vision becomes blurry, spotty or hazy.

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